Distillation control apparatus



w. J. PODBIELNIAK 2,275,648

DISTILLATION CONTROL APPARATUS Marh 10, 1942.

5 Sheets-sheet 1 Filed Aug. 2l, 1940 March 10, 1942. w. JQ PODBELNIAKDISTILLATION CQNTROLY APPARATUS Filed Aug. 21, 1940 5 Sheets-Sheet 2 imwgwen/02?' March 10, 1942. w PQDBIELNIAK 2,275,648

DISTILLATION CONTROL `APPARATUS Filed Aug. 2l, 1940 5 Sheets-Sheet` 5March 10, i942.

w. J. PoDBn-:LNIAK 2,275,648

DISTILLATION CONTROL APPARATUS Filed Aug. 21, 1940 5 Sheets-Sheet 4 /QQZ Z March 10, 1942 w. J. PODBIELNIAK DISTILLATIN CONTROL APPARATUS FiledAug. 2l, 1940 5 Sheets-Sheet 5 Patented Mar.` 10, 1942 2,275,641;msrrLLA'rroN coN'raoL APPARATUS Walter J. Podbielnixtk,` Chicago, Ill.,assignor to Benjamin B. Schneider Application August 21, 1940, serialNo. 353,462

(ci. 2oz-16o) 33 Claims.

The present invention relates to improvements in fractionaldistillation, and more particularly to the control of the operatingconditions, especially of reflux ratios, rates of distillation, and thelike, in precise fractional distillation. It is an improvement over theinvention described in my prior Patent No. 1,967,258, granted July 24,1934. The apparatus in accordance with the present invention'lendsitself particularly for use for analytical purposes, as in the analysisof constituents of natural gas, natural gasoline, cracked gasoline andother petroleum distillates and of mixtures of other volatile materialssuch as chlorinated hydrocarbons, alcohols, ethers, aromatichydrocarbons, manufactured gas, coal gas and the like.

In my prior Patents Nos. 1,917,272, granted July 11, 1933, and2,009,814, granted July 30, 1935, and in my prior application Serial No.303,434, filed November 8, 1939, I have described precisionfractionating columns, particularly intended for analytical purposes andmethods of distillation in connection with the operation thereof,whereby the precisc-analyticaldistillation of mixed liquids or liqueablegases may be effected conveniently and rapidly, and an accuratedetermination of the individual constituents of said mixtures made. Inaccordance with the present invention, in the operation of suchprecision distillation columns, I secure an automatic control of thedistillation operation as a whole, as Well as a perfect and automaticcontrol of the conditions within the columns themselves. I am alsoenabled-to secure directly and automaticallypa complete record of thedistillation corresponding to the usual fractional distillation curveand giv`- ing directly the relationship between temperature and quantityof material distilled, `in contradistinction to the usualtemperature-time curves ordinarily securedin such operations. By the 4apparatus in accordance with the present invention, I amable tomaintain' the progress of the upper reflux portions, respectively, ofthe fractionating column, with parts in elevation and broken away;

Fig. 4 is a transverse sectional view taken substantially along the line4-4 of Fig. 3;

Fig. 5 is an enlarged, detail longitudinal sectional view through thehydraulic, distillation rate control and shut-off mechanisms of theapparatus, with parts in elevation and broken away;

Fig. 6 is an enlarged fragmentary, longitudinal sectional view through.the shut-of! mechanism taken substantially along the line 6--6 of Fig.5;

Fig. 'I is an enlarged, detail, longitudinal sectional vew of thedistillation rate control valve showing the means for varying .the rateof distillation;

Figs. 8 and 9 are horizontal transverse sectional views thereof takensubstantially along the lines v8 8 and 9-9, respectively, of Fig. 7;

Fig. `10 is a sectional, detail view of a solenoidoperated valve for thecontrol of the water line to the distillation rate control portion oftheapdistillation, after it has been started, substantially automatic.

The invention and the advantages thereof will .45

be fully understood from the following description of the hydraulicdistillation control apparatus 4in accordance with the presentinvention, illustrated by the accompanying drawings, in

which: i f

Figure l'is a general view, partly in elevation and largelydiagrammatic, of a layout of apparatus suitable for carrying theinvention into effect; Figs. ,2 and 3 are enlarged, detail, longitudinalparatus;

Fig. 11 is a sectional, detail view through a solenoid-operated valvefor the control of the supply of cooling medium to the fractionatingcolumn;

Fig. 12 is' an elevation of a graduated valve wheel which is provided onthe stems of the manually operated valves of the apparatus in accordance with the present invention;

Fig. 13 is an enlarged fragmentary diagrammatic view cfa modifiedfractionating column and control mechanism in accordance with myinvention;

Fig. 14 is a representation of a partial distillation curve produced bythe apparatus in accordance with my invention utilizing the modifiedfra-ctionating column and control mechanism of 0 Fig. 13; and

Fig. 15 is a perspective view, largely diagram -matic, of a temperatureresponsive control mechanism in accordance with my invention.

Referring more particularly to the-drawings, the numeral Ill indicates,generally, a fractional distillation column which is substantiallysimilar to the column described in my prior application Serial No.303,434 above` referred to. While I prefer to carry outthedistillati'ons in this type of column, it is, of course, to beunderstood that the columns of my prior patents above referred to, asWellasother columns, may be used in lieu thereof.

This column structure (Figs. 2 vto 4), as illussectional views throughthe lower distillation and 5 5 trated, is provided internally with anelongated distillation column or tube I2 surrounded by an evacuatedjacket member I4, slightly spaced from the tube, as shown at I6,substantially throughout the length of the tube. Both distilling tube I2and jacket I4 may be suitably formed of a low expansion, heat-resistantglass, such as that commercially known as Pyrex, or of quartz or othersuitable material. Spaced between the walls of the jacket member andmounted on wire supports having a low thermal conduction is a reflectormember I8 which extends substantially throughout the length of thevjacket as shown in the drawings and as more fully described in my priorapplication above referred to.

The distillation tube I2 may have any suitable dimensions, for example,one to six feet in length and, preferably, an internal diameter of fromabout 2.5,to about 3.5 mm. and up to about mm. except for the lowerenlarged extremity 20 which constitutes the distilling bulb into whichthe sample to be distilled is introducedthrough an inlet tube 22. Withinthe limits of internal diameter of the distilling tube as set forthabove, capillary action is most effective in bringing about 4,

sired. Tube I2 may be provided with a packing 24, suitably in the formof a coil or coils of small wires, or of a closely spaced wirestructure,` for the purpose of aidingin bringing about the more extendedand intimate surface contact of the downwardly flowing reflux liquidwith the vapors rising from the distilling bulb 20.

sample inlet '22 is in the form of a glass tube which extends throughthe base of the distilling bulb and is sealed in place therein. Thedischarge end 26 thereof is well above the liquid level of the sampleintroducedinto the bulb for distillation and is so arranged that liquidcondensate formed in tube I2 'and collecting in bulb 20 cannot back upinto the entering tube and ultimately freeze and crack the stop-cockwhich controls the flow of samples from the sample containers. l

A second glass tube 30 is sealed into the bottom of bulb 20 and servesto establish communication between the bulb and a mercury bottle (notshown) or between the bulb and a graduated receiver, (not shown) forthevpurposes fully described in my prior application above referred to.

The space between the upper portion of distilling bulb 28 and the innerwall 32 of jacket I8 is substantially plugged with a gasket 34 whichcloses :the bottom of passageway I6.

Heat may be supplied to the sample in. the distilling bulb 20, forexample, by the metal-clad, cartridge-type, electric resistance heater36 which extends into an off-centered glass heater well 38 formed in thebottom of the bulb. The current supply wires 40 of the heating elementlead to a conventional rheostat (not shown) which l may be controlled toregulate accurately the heat input to the liquid portion of the samplein the bulb in order to effect a desired rate of vaporization. pObviously, any other suitable heating means may be employed for thispurpose.

.At the upper end of the column, the evacuated jacket I8 is enlarged, asat 42, to provide a space between the inner wall of the jacket and thedistilling tube I2 for a metal reflux chamber or vessel 44 into whichliquid air is introduced for cooling the distilling tube to condensevapors therein and provide reflux. Vessel 44 may be, suitably, in theform of a double-walled, annular container which may, if desired, befilled with suitable packing and provided with chambers and bailleplates (not -shown) for -the purpose of controlling and distributing theow of liquid air vapors rising therein. Also, if desired, there may beplaced in the vessel a suitable material having a high specific heat,for example, glass beads as described in my prior Patent No. 1,917,272.Vessel 44 is supported in the reflux portion of the column,`as by theglass wool insulating material 46 which is packed around the distillingtube and rests on a shoulder 48 formed in the inner Wall 32 of theevacuated jacket. The vessel'is additionally supported by insulationmaterial 68, suitably asbestos, which is positioned between theperiphery of the outerwall of the vessel and the inner wall of theevacuated jacket.

Vapors rising in the distilling tube from the boiling liquid in thedistilling bulb 20 are cooled and condensed to provide reflux, as by themedium of vaporized and/or unvaporized liquid air supplied to passagewayI6. The liquid air is supplied from a thermos bottle 52 containing'liquid air which ,communicates with vessel 44 through a vacuum-jacketed,silvered tube 54. The liquid air introduced into the vessel becomesvaporized and the vaporized liquid air flows out of the top of thevessel and down through the space between the inner wall 56 of thevessel and tube I2, through packing 46 and into passageway I6. Ifdesired, the inner wall 56 of the vessel may be perforated, as at 58 toprovide openings through which unvaporized liquid air may spill overinto passageway I6 to provide additional Vcooling means for thedistilling tube for purposes of producingrefiux and for condensingvapors in the lower portion of the tube as fully described in my priorapplication above referred to. The vaporized and, if desired,unvaporized liquid air, flow down through -passageway I6 to the gasket34 and the vapors discharge to the atmosphere through a moderatelyflexible, spiral glass coil 60 which is joined to the inner wall of theevacuated jacket, as at 62.y Coil 60 has an upwardly extending conduit64 which passes through anv opening in reflector I8, as at 66, andpasses out of the column through an opening in the outer wall of theevacuated jacket as at 68.

The top of the distilling column is closed by a seal or plug 10 throughwhich theupper extremity of distilling tube I2 and one extremity ofevacuated tube 54 extend.

Fractionated vapors passing. out ofthe distilling tube flow through avapor outlet line I2 which communicates with a selective manifoldarrangement, referred to generally by the numeral 14, which, through themedium of threeway, stop-cocks 16, for example, may distribute thevapors as desired throughout the apparatus as hereinafter described andas is fully apparent from the drawings. In practice, the vapors passingthrough the vapor outlet line 12 enter the selective manifoldarrangement and are directed to the vapor line 18 which ,communicateswith the bottom of thedistillation rate control mechanism, referred togenerally by the numeral 80, which will be fully described hereinafter.communication between the vapor outlet line 12 and vapor line 82 leadingto manometer 84 which indicates and controls the pressure conditionsprevailing in the column. The vapors passing through the bottom or valveportion of the distillation rate control mechanism 86 are in turnconducted through the automatic shut-off valve,

The manifold also serves to establish.

, tion.

designated generally by the numeral 86, and then through the return line88 leading tothe selective manifold '|4. Line 88 communicates with thevapor receiving -section of the manifold through stock-cock 90 and thevapors flowingl therethrough may be directed, as desired, to one of thevapor receivers 92, 94, 86, 98 and |00 by manipulation of vthestop-cocks. Connected as shown, vapor in line 88 will ow into receiver'92 through stop-cocks 90 and |02.

Eachof the receiversfor the vapor is main- `tained under a reducedpressure and at a temperature such that the contents thereof are kept invapor form as fully described in my prior patents hereinbefore referredto. Each receiver is of xed volume and the increase of pressure thereinresulting from the inflow of vapors evolved from the distillation columnis indicated by a manometer |04. Thus, as shown, receiver 92 is incommunication ,with line |06 through stock-cock |08, and line |06, inturn, with manometer |04. It is apparent from thev drawings that by asuitable manipulation of the stopcocks communication can be established`between any of the receivers and manometer |04 to determine the pressureof the vapors withinthe receivers at any time. Manometer |04 functionsadditionally in controlling the operation of the distillation ashereinafter' more fully set forth.

At the beginning of distillation of a sample to be subjected toanalysis, for example, natural gasoline, a compensating bottle ||0,conveniently housed in the same water bath as the vapor build uppressure Within the column to approximately atmospheric or otherwise, asfound desirable for the particular material under treatment.

ents Nos. 1,917,272 and 2,009,814 above referred to. The distillationhavingbeen initiated, its

progress is automatically controlled in accordance with the presentinvention as fully set forth hereinafter.

`Manometer 84 is sensitive to pressure conditions in the column, throughline 12, the selective manifold and line 82, as hereinbefore set forth.As is apparent fromthe drawings, ma-

nometer 84 is suitably of the U-tube type with receiver bottles, isequalized to atmospheric conditions through a vent and a stop-cock (notshown). Compensating bottle H0; is in com-'- munication with the closedend .of the left hand arm ||4 of the manometer |04 through `the line ||2and. in consequence, the conditions in the space above the mercury intheleft hand arm ||4 are equalized with those in the compensating bottle||0. The compensating bottle is now closed to the air and the system isthus made independent of changes in' barometric pres- |04 and with line88, as shown-in the draw-.

ings. l

After the system is evacuated, distillingcolumn |0 is isolated byturning stop-cock -16 and the column is cooled by supplying a coolingmedium such as liquid air'to cooling vessel 44 and passageway I6. Thesupply of liquid air to passageway |6 is controlled by acompressed airsupply line |20 in which are a pressure regulator |22, a control valve`|24 and a regulating throttle valve |26. The operation and construcaclosed leg |21, with which line 82 communicates, and an open leg |28.Within the manometer is a suitable liquid, for example, mercury, whichis connected by av suitable conductor wire |30, passing through .theglassof the tube, with one pole of a suitable source of. electricity. Asis apparent, an increase of pressure in the column forces the mercury inthe manometer upwardly in the open leg |28.

Extending into the open leg |28 of the manometer are a pair of contactrods |32 and |34. The lower extremities of the contact rods are setapproximately 2 to 5 mm. apart, the extremity of rod |32 being higherthan thecorresponding extremity of rod |34. These wires or rods-are setin the open arm of the manometer so that their lower extremitiesstraddle the pperating level of the mercury. Contact rod |32' isprovided with an electrical connection |36 leading to the valve |24 inth'e compressedair supply line|20,' and contact rod |34 is provided withan electrical connection |31 leading to a valve 256, through either line|31-a or line |31b, a switch block 3|3 and a line 303.

Valve |24 is of the'conventional electromagnetic solenoid operated,normally closed type and opens to permit the flow of compressed airthrough line |20 wh'en the rising level of the mercury in the open leg|28 of the manometer contacts rod |32 and closes the circuit. Althoughin scale in Fig. 10. 'I he solenoid operates the contion of controlvalve |24 will be described hereinafter: WhenV the desired cooling`has\been effected, the 'sample to be subjected to distillai tionA isintroduced into distilling-bulb 20 and the stop-cocks at the bottom ofcolumn |0 are closed, as fully described in myg-p'rior applicais usuallystill somewhat below atmospheric, and

At this time the pressure in the column heat is supplied through theheatingv element 36 to effect vaporization of the sample and to icalvalve member or plug |38, which' is normally held against its valve seat|40 by spring pressure. On operation of the solenoid the valve opens andpermits a ow of compressed air through line |20 f and into bottle 52toforce liquid air into passageway` |6to 'cool and restore the pressurewithin the poluilm to normal. The column of mercury in alim |28 lqwersresponse to this decrease of `pressure in the column until contact withrod |32 i'sybrokem The valve controlling the supply of compressed air tobottle 52 then returns to its y normal closed position.

The operation of the valve member |38 in th'e manner hereinbeforedescribed causes thesupply cf a-substantial additional quantity ofcompressed air to-bottle 52 and of a corresponding additional supply ofcooling medium to the reux chamber and passageway in the column. I havefound it convenient to provide a pressure gauge |44 to :indicate thepressure of the air in the compressed air line |20. To preventlovercooling, I have found it desirable to provide a minute, continuousvent or leak of air from bottle 52, for example, through vent line |42communicating with line |20 and provided with an adjustable valve |43whereby the residual compressed air remaining after each cessation ofthe air supply may be rapidly vented.

In actual practice, to effec-t smoother and more nearly continuouscooling, I provide, in the electrical connection |36, a conventional,motor-driven, circuit interrupter device, indicated generally by th'enumeral |46. This interrupter device serves to make and break thecircuit periodically so that, when operated, valve |38 is opened andclosed intermittently to permit successive small puffs" or surges of airto flow through the valve |24 and line |20 into bottle 52, instead of arelatively large surge as would be the case if no such circuitinterrupter device were provided.

If desired, additional provision may be made in connection withmanometer 84 to operate emergency signals in the event of an excessiverise in pressure in the distillation column, notwithstanding reuxcooling. For this purpose,I as in my prior Patent No. 1,967,258, forexample, an additional contact rod (not shown) may be provided in theopen leg |28 with the lower extremity thereof somewhat higher than thecorresponding extremity of contact rod |32. Inthe event that the mercurycolumn in the open leg |28 contacts this rod due to excessive rise inpressure, a circuit (not shown), similar to the heretofore Iliescribedelectrical circuits, including this rodA is closed and a signal devicewithin the circuit, which may be either an auditory signal, such as abuzzer, or a visual signal, such as a light, or both, is caused tooperate -to draw the attention of the operator to the emergencyconditions existing in the system. Reference may be made to my priorPatent No. 1,967,258, above referred to,for a complete showing anddescription of the emergency signal construction and operation. Ifdesired, the contact rod in the emergency signal circuit may beelectrically connected to-the heating cartridge 36 and may be operative,through a relay, to dlisconnect the4 heat input to the distill'ing bulbwhen the mercury contactsthis rod. In this manner the operator will beaided by a reduction in the rate of rise of distillation pressure withinthe column, thus giving the operator more time to correct conditionsbefore the-mercury may be forced out of the open leg |28 of manometer84.

In order to secure a record of th'e temperature at which the variousfractions pass out of tube I2 in vapor form, I provide in the upperportionthereof a thermo-couple (not shown), as in my prior Patent No.1,967,258, connected in the usual manner by connectors |48 and |49 tothe terminais |48A and |49B of a recording pyrometer |50, suitably ofthe potentiometer type, the distiL lation curve recording pen thereofbeing indicated by the numeral |52. As suchA pyrometers are of a typewell-known in the art, the detailed mechanism thereof is not shown. Pen|52 operates with rise in temperature upon a traveling paper sheet |54to chart the distillation curve |56.

In the operation of such recording pyrometers,

it has hitherto been customary to cause the paper sheet |54 to be movedby clock-work or other constant speed motor and thereby cause the papersheet to'travel at a constant rate `of speed. IIhe record made on thissheet indicates not only th'e temperature of the device under operation,but also the time at which the record is made. In accordance with thepresent invention, however, I provide means whereby the feed of papersheet |54 is controlled in accordance with the quantity of vapor passingover, through the pressure rise in the fixed-volume containers, forexample, receiver 92, in which the vapor fractions are received andmaintained in vapor phase at a substantially constant temperature. As aresult, a record made upon sheet |54, showing the'temperature ofvaporization of the successive vapor fractions in relation to theiramount, provides at once an analytical distillation curve of thematerial undertreatment. The mechanism suitable for this purpose isshown on th'e drawings in Fig. 1

As hereinbefore set forth, manometer |04 is in direct communication withvapor line `|06 leading to the 2 receiving bottles, for example,receiving bottle 92. Manometer |04 is substantially similar in form tomanometer 84,-a `closed arm or leg ||8 being in communication withreceiver 92. This manometer also contains a column of mercury or -othersuitable conductive liquid which is connected through a suitable con-@ductor with one pole of a suitable source of electricity.

As successive increments of vapor pass from the distillation column intothe receiving bottles, f for example, bottle 92, they causecorresponding increases in pressure therein. These increments ofpressure are made to cause a corresponding feed of the paper sheet |54of the pyrometer in the following manner.

The paper feed roll |5| of pyrbmeter |50 is mounted upona drive shaft|58 which is driven by a gear motor |60. Shaft |58 extends through themotor and is provided at the extremity. thereof-with a pinion |62 which`meshes with'a rack |64 normally forced downward by the weight of therackA and/or a spring |66. The driving connection between the motor andthe pinion |62 is is, of course, apparent that clutch |68 permits therelative independent adjustment ofthe paper feed roll |5| and the rack|64. After the adjustment is made, clutch |68 is closed. Secured to theupper extremity of rack |64 is a crossbracket'l10 which is designed togrip and -hold an elongated, metallic contact rod |12 as at |14. Contactrod |12 extends downward into leg ||4 of manometer |04 through ,astufiing box |16 at the top of the leg, thereby closing the leg. Contactrod |12 is initially positioned so that its lower end is, in its normalposition, -but a very slight distance above the mercury column, say 0.1mm. When motor |60 is driven to operate shaft |58 and move the papersheet 54, rack |64 is raised upwardly and contact rod |12 risestherewith.

As heretofore pointed out, the pressure in the receiving bottles, forexample, receiving bottle 92, is communicated through the selectivemanifold to line |06 and legA ||8 of manometer |04. On increase ofpressure in the receiving bottle, the mercury in the manometer is causedto rise in leg ||4 and-contact with the rod |12, whereupon a circuit isclosed through the mercury, contact rod |12, connector |18, motor |60,and the connector |80 to the opposite pole of the so'urce of currentsupply. Motor |60-is thereby energized to operate shaft |58 and the feedroll effected by a manually operated clutch |68. It

andere of the paper sheet of the recorder. In doing so, rack |64 ismoved upwards, rod |12 raised out of contact with the mercury in leg ||4and the circuit through the motor is broken and the operation thereofceases. At the same time that the movement of paper sheet |54 has beeneffected in this manner, pen |52 operates to indicate upon the papersheet the temperature in the top of column I0. 'I'he paper sheet is madeto bear a record showing the temperature at which various vaporfractions are permitted to pass from the top of the lcolumn and thequan-v tity of such fractions. 'Ihe resulting record is thereby made toappear directly in the form of the usual distillation curve |56. It isapparent from the foregoing 'and from the drawings that paper sheet |54unrolls in an exact `ratio to the rise of rack |64. In actual practicethis ratio is tillation curve formed in response to the pressureincreases in receiver 92.

As heretofore .pointed out the rate of flow of vapor from thefractionating column I0 is controlled by two valves, in series; one thehydraulic operated distillate rate valve 80 and the other the hydraulicoperated shut-off valve 86. The construction and operation of thesevalves will now be described.

The hydraulic operated distillation rate valve (Figs. 5, '7, 8` and 9)comprises a valve body |88 provided with a recess as at |90 into whichthe in the order of about 2 to 1. It is also apparent i that this actionis intermittent since when the rising pressure in receiving bottle 92urges the mercury into contact with rod 12, the motor |60 is energizedto raise the rod |12 out of contact with the mercury and thereby breakthe I circuit. As ,distillation proceeds and the prescompleted at whichtime clutch |66 is disengaged and rack |64 lowered.

The recording instrument is also provided with a pen |82 which isdesigned to draw a distillation rate curve |84 on the paper sheet as itunrolls. Distillation rate curve |84 is in the form of a straight lineparallel to the edge of chart |54 jogged at xed time intervals, sayabout one minute. 'Ihe jogging of this curve may be eifected as by asuitable motor (not shown) connected to the pen or by a connection fromthe pen to the potentiometer motor as is Well understood in the art.Curve |84 provides a means for indicating and recording the distillaterate at any stage of the analysis with reference to the distillationcurve |56.

Should the operator decide to stop entering the vapors into receivingbottle 92, for example, and have the vapors enter into receiving bottle94, for example, during the course of distillation, it is necessary tofirst shut off connection |06 leading to leg ||6 ofmanometer |04. Thismay 'be accomplished by a suitable manipulation of the stop-cocks in theselective manifold although it is preferred that it be accomplished byclosing shut-off valve 86 as hereinafter described. Connections are thenmade from line 'I2 leading from the column to receiving bottle 94 by asuitable adjustment of stop-cock |86 in the selective manifold. Theshaftof motor |60 is now disengaged by the clutch |68v and pinion |62released from rack |64. Shut-off valve 86 may now be opened, therebypermitting the inercury in manometer |04 to come to equilibrium with thepressure in the connected receiving bottle 94. 'I'he operator thenplaces pinion |62 on the rack |64, which in the meantime was lowered bythe Weight of the rack and by spring |66, engages the shaft of the motorthrough clutch |68 and proceeds with the distillation. The section ofthe distillate curve made in response to pressure increases in receivingbottle 94 is added upon the end of the preceding section of thedisneedle seat member |92 is inserted and secured as by, for example, adrive fit. Needle seat member |92 is provided with -an internal bore |94through which vapors from line 18 are adapted to ow. The upper end ofbore |94, at |95 receives the needle valve |96, of special construction, to control the quantity of vapors flowing through the bore orValve seat |95. The .diameter of the needle valve 96, except for thelower extremity thereof, corresponds with the diameter of bore |94. Thelower extremity of the needle valve is tapered as -at |98 to permitvarying amounts of vapor to flow past the needle seat |95 depending uponthe position of the needle with respect thereto. The length of the tapermay vary as desired, although I prefer that it be in the order of aboutone inch long. The taper is preferably calculated to be such as to makethe change in rate of flow through the valve exponential. With theneedle in any particular position, for example, the position shown inFig. 7, controlled amounts of vapors are permitted to flow through bore|94 to the bottom of recess |90.

Member or plug |92 is recessed-or led down -at its top, as at 200, andalong one side, as at 202, to provide a passageway 204A for the ow ofvapors from bore |94 to -a discharge tube 206 leading to the lowerextremity of the shut-olf valve 86. The stem |91' of needle valve |96extends through a bore |94 in an extension 208 from valve body |96, andthe upper untapered extremity of the stem of the needle valve is held ina rod 2|0, as by a drive lit. The rod 2|0, in turn, is secured, as by adrive fit, to a follower 2 2 `which extends up into a water-tight vesselor pot 2|4. Within pot 2 |4 and surrounding needle follower 2|2 is a.bellows assembly comprising an expansible bellows (preferably metallic)2|6 and Y an actuating member 2|8 secured to the'bellows stem 2|0 withvapor-tight fits.

and having a centrally disposeddepending sleeve or guide 220 into whichthe upper extremity of follower 2|2 enters and is secured. Within thebellows assembly and surrounding 220 is av coiled spring 222 whichnormally acts to raise the ac-4 tuating member 2|8 of the bellowsassembly towards the-top of pot 2 4 and thereby raise needle valve |96.The pot 2|4 is provided with a water inlet 224 anda water outlet 226.

To prevent the vapors within the bore 94 from passing out of the systemthrough the .bore in extension 208, a tube 228 of rubber or othersuitable elastic material, such as Neoprene, is provided which issecured to the upper extremity of extension 206 and the lower extremityof valve The valve body |88 is secured to the under side of the pot 2 |4and supported by supports 230.

Mounted on the rod 2|0, suitably by a collar 232, is a pointer 234 whichmoves with the needle valve and which serves to indicate the position ofthe needle valve with respect to its seat. Thus, the position of thepointer along the vertical edge of chart 236 indicates the position ofthe needle valve with respect to its seat. For conf venience of theoperator, curves may be provided 'mechanism of the distillation ratevalve hereinabovedescribed, they pass through conduit 206, through aflexible conduit or tube v24|), suitably formed of artificial rubber,Neoprene or the like,

Ythrough line 88 and into the receiving bottles.

'I he flexible tube 240 constitutes in effect a valve which is closed bythe action of water entering inlet 242 of a water-tight pot 244 housingan expansible bellows 246. Incoming water compresses bellows `246 andurges plunger 246 and follower plate 250 downward to compress the tubebetween plate 250 and a lower plate 252, which is` supported by bolts254 threaded into the bottom of pot 244.

The operations of the valves 80 and 86 control the rate of distillation,as will be apparent from the following:

When the mercury in leg |28 of manometer 84 fails to make electricalcontact with the lower wire |34, solenoid valve 256 (Fig. 11) isde-energized and is opened by the action of spring 258 urging valve 260away from its seat. Water from the water supply line 262 is then causedto flow through water strainer 264, water pressure regulating valve 266,through line 261, through hand control valve 268, through line 269 andthrough the solenoid v-alve 256. From valve 256 the w`ater. is divertedinto two branches, one flowing through line 210 to the inlet 242 oftheshut-oil? valve 86 and the other through line 21|, hand control valve212, check valve 213 and line 214 to the inlet 224 of the rate valve 80.These two ows of water are so proportioned, by hand control valve 212,that almost the full stream of water passes into the "shut-on valve 86,thereby quickly closing valve 240, and a reduced stream flows into ratevalve 80 to close it at a relatively slow rate. It is, of course,apparent that water entering inlet 224 of rate valve 80 urges bellows2|6 downwardly against the action of spring 222 and thereby urges needlevalve |96 into bore |94 to close the valve.

1/5" C. during the distillation of a' particular compound, an electricalconnection 218 from the potentiometer recorder actuates a temperatureresponsive solenoid valve 280, similar to valve |24, to open it andcause the water to ow from the inlet line, through line 269, line 282,through valve 280, through line 283, through hand adjustable valve 284,through check Valve 285, through line 286, through common line V214 andinto inlet 224 of the rate valve 80, thereby closing the rate valvetowards its minimum setting 1, 10 and 11 of my prior Patent No.1,967,258,

may be used for this purpose if the recording potentiometer is of thetype shown and described in that patent. I prefer, however, to use themechanism shown in Fig. 15 herein. This mechanism, in the main, is ofconventional design, construction and operation and is a part of thewell-known recording potentiometer sold by the Brown Instrument Companyof Philadelphia, Pennsylvania. In consequence, no more of the Brownpotentiometer recording mechanism is shown in Fig. 15 than is suflicientto show and explain the type of control mechanism connected thereto foruse .in accordance with the present invention.

Referring to Fig. 15, there is shown aconventional galvan'ometer 325such as is used in nullpoint automatic balancing potentiometerrecorders. The galvanometer is suspended between an upper and lowersuspension strip 326 and 321, respectively. The numerals 328 and 329refer, respectively, to the upper and lower electrical leads to thepotentiometer circuit. Galvanometer pointer 330 swings beneath thestationary upper table 33| of the conventional chopper mechanism, andbetween the side limiting table supports 332 and 333. In operation,pointer 330 is periodically clamped against table 33| by the risingmovable stepped-table 334 of the chopper 'mechanism The upper edge 335of table 334 When, due to natural functioning of the fraci tionatingcolumn, the pressure in the distillation column |0 builds up sulicientlyto urge the mercury inleg |28 of manometer |04 into contact with rod.|34, solenoid valve 2'56 .is energized and closed and no more waterflows to either the shut-01T valve 86 or the distillation rate valve 80.Thereupon, the shut-01T valve 86 opens at a'relatively rapid rate due tothe action of the elastic bellows urging the water out of pot 244',

331, the lower the limit to which the table may rise before clampingpointer 330.

.Table 334 is provided with rearwardly extending arms 338, having freeends which are secured to shaft 339. Shaft 339 and table 334 areoscillated by a crank 340, secured to the motor shaft of a constantspeed motor 34|', through the medium of a link 342 and a'follower arm343. Arm 343 is kept tightly against a pin 344, carried by link 342, asby a spring 345. y

collected in succeeding receivers, for example, one

chopper mechanism to effect opening and closing of valve 280 as follows:

I secure to one end of shaft 339 a. crank arm 346 which servesv toindicate the position of movable table 334 with respect to stationarytable 33|. On upward movement of arm 346, the free lend thereof strikescontact arm extension 341 point corresponding to a pointer deflectionto` the left of zero point 331 of stationary table 33|, corresponding toa temperature rise in the column of about 1/so C., when movable table334 clamps pointer 330 in this position. It is, of

course, to be understood that contact arm 348 is insulated from itscontacts. This contact varm is made of a suitable springy metal or metalalloy and the dimensions thereof are such that a further rise of movabletable 334 beyond that suilicing to make electrical contact between con,tacts 350 and 35|, as described, will merely place more pressure on thecontacts without distortion of the parts or interference with themovable table action.

fraction in receiver 82 and one in receiver 94, the column is firstclosed off from the system, and connection |06 leading to leg I I8 ofmanometer |04 is closed by suitable manipulation of the stopcocks. Thesefractions are usually cut at various points along the conventionaltemperature scale (not shown) of the recording potentiometer |50,corresponding to, for example, the methaneethane, ethane-propane, etc."cut points. In my preferred practice, I close-off or Vshut-,in thecolumn during this change over from one receiver to another by closingshut-oil valve 86. This may be accomplished by means of a suitablemanually operated switch 300, in electrical line |31, which may beopened to de-energize valve 256 and thereby permit water to flow intoshut-olf valve 86 as hereinbefore described; however, I prefer that itbe accomplished automatically as follows:

Positioned above Athe recording potentiometer |50 and extendingsubstantially the full length It will be obvious from the foregoing thatwhenever the temperature rises even a small fraction of a degree C., asreected by the galvanometer pointer deflection to the left of zero, theaction of the arm 346 in closing contacts 350 and .35| will groundelectrical line 216 and cause valve 260I to function as described above.However, any drop-of temperature in the column will not effect valve 280since in such cases, contacts 35IL and 35| remain open, and thecontact'arm 346 'will simplyI rest on a support, as at 352.

Opposing these two closing actions of the rate valve 60 hereinabovedescribed, one due to a drop in pressure in the column and the otherto-a rise in the redux-temperature ofl the column, is a continuous leakof water from pot 2 I4, through outlet 226, through line 286, throughadjustable valve 260, preferably a needle valve, and out through thewater drain 211. Thus the rate valve continuously tends to recover fromits closed position at a relatively slow rate.

The distillation rate controls hereinabove described are the maincontrols whichfunction automatically as already described to control therate of distillation. In addition to these main controls, there are twoauxiliary distillation rate controls which also function automaticallyto control the rate of distillation, but which are used separately andindependently, when desired, during certain stages only of thedistillation as here:- inafter described. Y

During the course oIfy a fractional distillation as heretoforedescribed, `when gas fractions are of the conventional temperature scale(not shown) of the recorder is a guide bar 30| carrying thereon amovable, contact switch block 302 which can be manually positioned atany desired point along the bar. The switch is included in a circuit foractuating valvel 256 through electrical line 303 and manually operateddouble pole double throw switch 3I3. Switch block 302 carries a movableinsulated switch lever member 301, spring-pressed to the position shown.Le'ver 301, in turn, carries a pair of contacts 301-a and 301--b whichcooperate with a pair of stationary contacts 306 and 3I0. Contact 300 isgrounded. Movable 4contact 301-a is connected 4by wire 3|I-a tocontacting blade 3|2--a of solenoid winding of valve 256 and thence tothe terminal. It is evident that when movable contact 301-b is movedfrom its closed position, as shown, that lines 303 will be de-energized,if not already de-energizedas heretofore described.

Referring back to switch 3I3,`contact 3I5 is connected by line 320 tothe solenoidwinding of valve 280, and thence to terminal.

In effecting closing of the shut-oif valve 86 during distillation topermit the introduction of the fractionated vapors into succeedingreceivers. it must be assumed -that the fractional distillation isproceeding along the boiling point plateau of a particular compound andthat the movable switch 302 has been positioned at the -cut point whichis intermediate 4between the boiling point plateau of that compound andthe 1 boiling point plateau of the next succeeding ccmpound, and thatmovable blade 3|2b has been throw-n in contact with contact 3 I 4. Whenthe rising' column reilux temperature eects travel of recording pen |52along recording sheet |54 to a position immediately below lswitch 302and coinciding with indicating lngery 304 thereof, as shown in thedrawings, an extension 305 from the pen carriage 306 bears againstmovable insulated switch lever 301 and acts, as above described, todisconnect valve 25'6 from line |31-a, leading to Aground through line|31. Valve 256 'now opens and water from the supply line 262 ilows intothe shut-off valve 86 to close it IS hereinbefore described. Theoperator now changes the receivers as described above and manually setsthe sliding switch 302 in the position along bar 30| corresponding tothe next higher cut point. This operation is continued untildistillation of the sample is completed.`

Movable switch su: may be used e150 to effect a more accurate control ofthe rate of distillation atl the break or transition point from oneplateau to the plateau of the next higher boiling component of thesample being distilled. Such control is optional, but is desirable inconnection with the separation by distillation of close-boilingcompounds such as iso-butane from isobutylene and iso-butanefrom'n-butane.

When switch 302 is used for this purpose, movable contact blade 3|2a ofswitch 13|3 is thrown over to engage contact 3|5, simultaneouslydisengaging contact blade 3|2=b. from contact 3|4 and connecting bladeSI2-h to stationary contact 3| 4-a. Contact 3|4-a is connected to line|31 through line |31-b, thus bypassing the switch 302. Switch302 is .nowpositioned alongv bar 30| at a point corresponding approximately to afraction of a degree. say,

distillation rate valve mechanism may be, and preferably is, constructedof such dimensions and precision of t that within its limits of travelit will meter from 1 to A300 cc. of gas per minute, approximately, withgas flows for specific hydrocarbons or other gases or vapors in cc.s perminute very closely reproducible against the positions of the plungerwithin its seat, as expressed Aby the calibration chart 236 shown inFig. 5l In order to retain this reproducibility it is desirable tomaintain the pressure of receivers 92, 94, 96, 98 and |00, at belowabout 50% of thel fractionating column pressure, or below Y the criticaldown-stream pressureI condition,

contact 303. It will be noted that inthe present position of switch 3|3,stationary contact 3|0 and line 3| I-b are electrically inactive. Valve230 now opens and the water from the inlet line flows into inlet 224 ofAthe rate, valve 3 0 as described above, thereby closing the rate valvetowards its minimum setting. -The improved fractionation in the column,resulting from a reduction in the distillation rate asa result ofclosing down the rate valve, reduces the reflux temperature to thepre-set boiling point plateau of the said compound being distilled. Thepen carriage 306 moves back slightly, carrying extension 305 away frommovable-contact 301 to break the circuit and to de-energize valve 230.Rate valve 30 now opens as hereinabove described.

In general it may be stated that the water flowing through inlet line231 is under a pressure in the order of about 24-to 26 pounds,I persquare inch. The hand operated lwater Valves 253, 234, 212., 213 and 230are suitably adjusted atthe start of the distillation operation to makepossible the functioning of the mechanism as hereinabove described. Careshould be exercised in connection with the adjustment of valve 213 sothat the pressure of the water passing therethrough does not fall belowabout 18 lbs. per

l square inch when the shut-off valve 33 is closed.

the periphery of the valve wheel into which a spring-pressed detent 236extends 4to prevent unassistedv movement of the wheel andA at the sametime serving as a pointer to indicate the` extent of opening.

The hereinabove described tapered nplunger below which further change indown-stream pressure does not affect flow of vapors or gases.

In general, it is possible to substantially fix the adjustments ofneedle throttling valves 284, 212 and 216, from experience, to providebest general operation of the hydraulic distillate rate controlmechanism. The rate leak valve 290 may then be adjusted, for desiredmode of control operation. For instance, if the valve 290 is openedwider, this results in a consistently quicker opening of distillate ratevalve 80, and thus a quicker recovery of distillate rate after everytemperature rise and after every drop of pressure in the fractionatingcolumn, which of course exerts a closing effect on rate valve 30 asalready explained above. The resulting control of the course of thedistillation analysis o would be to shorten distillation time, with acertain sacrifice of sharpness of separation (due vto reduced refluxratios used throughout as result of greater average opening of the ratevalve 30). Conversely, closing down on rate leak valve 2,90

would in effect increase and prolong the eii'ectA of every upwardtemperature fluctuation and every downward column pressure fluctuation,thus increasing reflux ratios at crucial points in the distillation withresulting improvement in separation and` accuracy, with howevercorresponding prolongation 'of total distillation time.

Similar control of control characteristics may also be obtained byvarying the settings of the other throttling needle valves, although ingeneral the effect of such variations is more com-l plicated and not asclean cut as variation of rate leak valve 230. i

'I'he functioning of lthis type of control is such vthat the distillaterate may be varied automatically over the entire range of hydrocarbonsor other gases from methane to hexane, for example, withglittle, if any,readjustments necessary during analysis,- to obtain sharpestfractionation of individual hydrocarbons during the resulting totaldistillation time. The mechanism will increase the distillate rate, on aplateau in the distillation curve, where the separation is//easy, andwill automatically decrease the rate, Kas required, on breaks where alow distillate rate (corresponding to high `reilux ratio) is required tominimize the size of the intermediate mixed fraction between purecomponentsl i The effectivenessv of this novel type of control,depending as it' does on the balancing of closing eiects on 'the'distillate rate, according to temperature rise and toY pressure fall,respectively,

against the constantopening eilect due to constant leak of water fromthe distillate rate bellows is such that for most analyses it is noteven necessary to fix the minimum and maximum distillate rate limits asheretofore,l although this is provided for as in Fig. 5, since this isaccomplished automatically by the hydraulic control for each hydrocarbonaccording to the pressure and temperature response and fractionatingpower of the particular fractionating column used. For example, shouldthe distillate rateon a plateau become too high, through the effect ofconstant lean of water from the distillation rate valve bellows, asexplained above, either the column pressure will begin to fall, or theoverhead temperature will begin to rise, either or both of these tendingto reduce the ydistillate rate in the manner already explained.Similarly, if the rate on a plateau is too low, it will open graduallyuntil limited as immediately explained. On break, where the temperaturewill rise despite the closing of the distillate rate valve, suicientvapor will still pass through the valve, which will slowly oscillatebetween its lowest possible position and a somewhat higher position, thelatter depending on adjustment of rate valve 290, to accomplish thedistillation of the intermediate fraction at high reflux ratio and inreasonable time.

It should also be pointed out that the so-called pressure response ofthe column, effecting the closing of the distillate rate valve in themanner already explained, is somewhat independent of the temperatureresponse of the column, which hitherto was the only control indicationused in this type of apparatus. When large boiling point differencesbetween gaseous components are involved, as between methane and ethane,the pressure response is more positive than the temperature response,and may in fact suiiice for satisfactory control action by itself.However, when the difference in boiling points of the gaseous componentsbecome less,` as in the case of isobutane and n-butane separation, ithasi been found that the pressure response alone is not suflicientlypositive or sensitive and that the" temperature response is essential.The temperature response indication is, however, of value throughout theentire distillation, in conjunction with the pressure response.

In the modified operation of thefractionating column shown in Fig. 13,two thermocouples aire provided in the upper portion of the column, one

above the other.l The upper one, 423, is normally located in the tubesubstantially as in my prior Patent No. 1,967,258. The lower one, 424,is located in the tube at a point somewhat below thermo-couple 423, say,inthe order of about one or one and one-half inches. The upperextremiconnectors |48 and.l |49' through a switch 425 A driven slowly,say at a speed of about 2 R. P. M., b'y the synchronous motor 42|.lSwitch 425 is arranged to alternately connect and disconnect the leadsfrom the two thermo-couples.

When the distillation is progressing' on .a

plateau as indicated by, for example, plateau' |56 of distillation curve|56, both thermo-couples alternately actuate pen |52 to recordidenadvance temperature indication causes electrical connection 218 fromrecorder I5U to energize valve 288 and open it to admit water toqrate ofthe distillation rate and establishes the desired distillation reuxratio considerably ahead of the time when the top thermo-couple wouldnormally perform the similar function. This actionpermits the apparatusto anticipate a temperature rise and to increase the reflux ratio farenough ahead of the actual break to improve the fractionation at thispoint. l i

The above will 4be apparent from a considera- -tion of the partialanalytical distillation curve |55A (Fig. 14) formed on thepaper sheet ofthe recorder when utilizing the modified column of Fig. 13. "When thedistillation is proceeding along a plateau, the temperature in thereflux portion of the column is substantially uniform and thethermo-couples actuate pen |52 to record the plateau line |56 of curve|46A (shown in full lines). As the break point in the distillation isapproached, the temperature in the reflux portion of the column beginsto rise and this rise is indicated initially by thermo-couple 424 whichtranslates` the temperature rise to the recorder andicauses pen |52 torecord this temperature on the sheet at, for example, point 421. Theswitch 425 then connects in the upper couple and consequently the nextposition along curve |46A indicates the temperature. in the column aboutthermo-couple 423, and since this thermocouple has not been affected, asyet, by the temperature rise, the pen is caused to move to point 428,'I'he alternate recordings of the temperatures in the column about thethermo-couples 424 and 423, respectively, resulting from the operationof switch 425, are shown by the zig-zag line. It will be apparent; fromthe foregoing that the .temperature rises in the column, as the breakpoint is approached, are indicated initially by thermo-couple 424, asindicated by the points in the distillation curve along the dotted line429, and the alternate points along dotted line 430 indicate thetemperature rises in the portion of the column about thermo-couple 423.It is thus manifest that by the aid of this 'novel fractionatingcolumn-valve 280 is energized to admit Water to rate valve 8|] invadvance of the time that valve 280 would be energized yif the columncontained but one thermo-couple as in' my prior Patent No. 1,967,258,and the sensitiveness and the accuracy of the operation are increased. i

Although the present invention has been described in connection with thedetails of specific method and apparatus embodying the same, it is notintendedthat these details shall be recarded as limitations upon thescope of theinvention, except in so far as included in the accompanyingclaims;

I claim:

1. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for coolingvalve 83, during the period that thermo-couple 424 is connected in byswitch 425, thereby closing it towards its minimum setting as describedthe upper portion thereof, a normally open, fluidoperated valve adaptedto control the rate of dis- Vtillationfgby controlling the flow ofdistillate vali/e to decrease the opening thereof vand thereby impedethe flow of distillate vapors from said column.

2. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for cooling 5ing the upper portion of said column with said valve, means responsiveto pressure change at the outlet of said columnto control said coolingmeans and a second means also responsive to pressure change at theoutlet of said column,

said second pressure-responsive means including a pressure-responsivedevice communicating with the outlet of said column, means actuated bysaid pressure-responsive device on decrease in pressure at the outlet ofsaid column to cause uid to flow into said valve to close it, meansactuated by said pressure-responsive device on increase in pressure atthe outlet of said column to cause fluid to flow out of said valve toopen it and means responsive to a temperature rise at the top of thecolumn from any previous temperature toycause fluid to flow into saidvalve to decrease the opening thereof and thereby impede the flow ofdistillate vapors from said co1- umn.

.3. In the apparatus set forth in claim 2 where- 30 in said secondpressure-responsive means is operable independently of said first-namedmeans responsive to pressure change.

4. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for coolingthe upper portion thereof, a normally open, fluid-operated needle valveoperable to control the rate of distillation by controlling the flow ofdistillate vapors from the column, a vapor line connecting the upperportion of said column with said needle valve and a second normallyopen, fluid-operated valve in communication with said 'needle valve,means responsive to pressure change at the outlet of said column tocontrol 45 said cooling means, means responsive to pressure drop in saidcolumn to control the ow of fluid to said valves to decrease theopenings thereof and means responsive to temperature rise at the top ofthe column from any previous temperature to control the ilow 'of fluidto saidneedle valve to decrease the opening thereof and thereby decreasethe lo'w of distillate vapors from said column.

5. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for coolingthe upper portion thereof, a normally open, fluidoperated needle valveoperable to control the rate of distillation by. controlling the flow ofdistillate 00 vapors from the column, a vapor line connecting the upperportion of said column with said needle valve and a second normallyopen, fluid-operated valve in communication with said needle valve,

means responsive to pressure change at the otg5 let of said column tocontrol said cooling means and a second means also responsive topressure change at the outlet of said column, said secondpressure-responsive means including a pressureresponsive devicecommunicating with the outlet 'i0 of said column, means actuated by saidpressure- .responsive device on decrease in pressure at the outlet ofsaid column to cause fluid to ilow into said valves to close them, meansactuated by said pressure-responsive device on increase in pres- 7" sureat the outlet of said column to cause fluid to flow out of said valvesto open them and means responsive to a temperature rise at the topv ofthe column from any previous temperature to cause uid to ow into saidneedle valve to decrease the opening thereof and thereby impede' changeat the outlet of said column to control said cooling means, meansresponsive to pressure drop in said column to control the flows of uidto said valves to decrease the opening of said second-named valvequickly and to decrease the opening of said needle valve at a relativelyslower rate, and means responsive to temperature rise at the top of thecolumn from any previous temperature to control the flow of fluid tosaid needle valve to decrease the opening thereof and thereby decreasethe flow of distillate vapors from said column.

7. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for coolingthe upper portion thereof, a normally open, fiuidoperated needle valveoperable to control the rate of distillation by controlling the iiow ofdistillate said pressure-responsive device on decrease in pressure atthe outlet of said column to cause a relatively unrestricted fiow of uidto flow into said second named valve to close it quickly and arelatively restricted flow of fluid to flow into said needle valve tocause it to close at a relatively slower rate, means actuated by saidpressure-responsive device on increase in pressure at the outlet of saidcolumn to cause a relatively unrestricted flow of fluid to flow out ofsaid second named valve to open it quickly and a relatively restrictedflow of fluid to flow out of said needle valve to open it at arelatively slower rate and means responsive to a temperature rise at thetop of the column from any previous temperature to cause fluid to owinto said needle valve to decrease the opening thereof and therebyimpede the flow of distillate vapors from said column.

8. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for coolingthe upper portion thereof, a normally open, fluidoperated needle valveoperablev to control the rate of distillation by controlling the flow ofdistillate vapors from the column, a vapor line connecting the upperportion of said column with said needle valve and a second normallyopen.

fluid-operated valve in communication'wlth said needle valve, meansresponsive to pressure change at the outlet of said column to controlsaid cooling means, means responsive to pressure drop in said column tocontrol the flows of fluid to said valves to decrease the opening ofsaid second-.named valve quickly and to decrease the opening ofL saidneedle valve a't a relatively slower rate, means responsive tovtemperature rise at the top of the column from any previousternperature to control the flow of fluid to vsaid needle valve todecrease the opening thereofand thereby decrease the flow ofdistillatevapors lfrom said column, and means for continuously bleeding fluid fromsaid needle valve whereby said needle valve continuously tends to returnto normal position.

9. In apparatus for precise, batch fractional distillation, a distillingcolumn, means for heating the lower portion thereof, means for coolingthe upper portion thereof, a normally open, fluidoperated needle valveoperable to control the rate of distillation by controlling the flow ofdistillate vapors from the column, a vapor line connecting the upperportion of said column with said needle4 valve and a second normallyopen, fluidoperated valve in communication with said needle valve, meansresponsive to pressure change atthe outlet of said column to controlsaid cooling means, a second means also responsive to pressure change atthe outlet of said column, said second pressure-responsive meansincluding a pressure-responsivedevice communicating with the outlet ofsaid column, means actuated by said pressure-responsive device ondecrease in pressure at the outlet of said column to cause a relativelyunrestricted flow of fluid to ow into said second-named valve to closeit quickly and a relatively restricted flow of fluid to flow into saidneedle valve to cause it to close at a relatively slower rate, meansactuated by said pressure-responsive device on increase in pressure atthe outlet of said column to cause a relatively unrestricted flow offluid to flow out of said second-named valve to open it quickly and arelatively restricted ilow of fluid to flow out of said needle valve toopen it at a relatively slower rate, means responsive to a temperaturerise at the top of the column from any previous temperature to forcefluidto flow into said needle valve to decrease the opening thereof andthereby impede the flow of distillate vapors from said column and meansfor continuously bleeding fluid from said needle valve whereby saidneedle valve continuously tends to return to normal position.

10. In apparatus for precise, batch fractional distillation, adistilling column, means for heatving the lower portion thereof, meansfor cooling the upper portion thereof, a normally open, fluid-operatedthrottling valve adapted to control the rate of distillation bycontrolling the flow of distillate vapors from the column, and a vaporline connecting the upper portion of said column with said valve, meansresponsive to pressure change at the outlet ofvsaid column todistillation, a distilling column, means for heatmittently cooling theupper portion thereof, a

normally open, fluid-operated valve adapted to control the rate ofdistillation by controlling the flow of distillate vapors from thecolumn, and a vapor line connecting the upper portion of said columnwith said valve, means responsive to pressure change at the outlet -ofsaid column to control said cooling means, means responsive to pressuredrop in said column to cause fluid to flow into said valve to close itand means responsive to a temperature rise at the top of the column fromany previous temperature to cause fluid to flow into said valve todecrease the opening thereof and thereby impede the flow of distillatevapors from said column.

12. In apparatus for precise, batch fractional distillation, adistilling column, means for heating the lower portion thereof, meansfor intermittently cooling the upper portionthereof, a normally open,fluid-operated valve adapted lto control the rate of distillation bycontrolling the flow of distillate vapors from the column, and a vaporline connecting `the upper portion of said .column with said valve,means responsive to pressure change at the outlet of said column tocontrol Isaid cooling means and means responsive to temperature increaseat the top of the column from any previous temperature to cause uid toflow into said valve to decrease the opening thereof and thereby impedethe vflow of distillate vapors from said column.

13. In apparatus for precise, batch fractional distillation, adistilling column, means for heating the lower portion thereof, meansfor `cooling the upper portion thereof, a normally open,

r fluid-operated needle valve operable to control the rate ofdistillation by controlling the flow of distillate vapors from thecolumn, a vapor line connecting the upper portion of said column withsaid needle valve and a second normally open, fluid-operated valve incommunication with said needle valve, means responsive to pressurechange at the outlet of said column to control said cooling means andmeans responsive to temperature rise at the top of the-column from anyprevious temperature to control the flow of fluid to `said needle valveto decrease the open ing thereof and thereby decrease the flow ofdistillate vaporsfrom said column.

14. In apparatus for precise, batch fractional distillation, adistilling column, means for heating the lower portion thereof, meansfor cooling the upper portion thereof, a normally open, fluidoperatedneedle valve operable to control the rate of distillation by controllingthe flow of distillate vapors from the column, a vapor line vconnectingvthe upper portion of said column with said needle valve and a secondnormally-open, fluid-operated valve in communication with said needlevalve, means responsive to pressure change atthe outlet of said columnto control said cooling means, means responsive to temperature increaseat the outlet of said column from any previous temperature to causefluid to flow into said needle valve to close it and thereby impede theflow of distillate vapors from said column and means operable onldecrease in temperature at the outlet of the column to cause fluid toflow from said needle valve to open it.

15. In apparatus for precise, batch fractional distillation, adistilling column, means for heating the lower portion thereof, meansfor cooling the upper portion thereof, a normally open, fluid-operatedneedle valve operable to control the. rate of distillation bycontrolling the flow of distillate vapors from the column, a vapor lineconnecting the upper portion of said column with said needle' valve anda second normally open, fluid-operated valve in communication with saidneedle valve, means responsive to pressure change at the outlet of saidcolumn to control said cooling means, a second means also responsive topressure change at the outlet of said column, said secondpressure-responsive means including a pressure-responsive devicecommunicating with the outlet of said column, means actuated by saidpressure-responsive device on decrease in pressure at the outlet of saidcolumn to cause a relatively unrestricted flcw of fluid to flow intosaid second-named valve to close it quickly and a relatively restrictedflow of fluid to flow into said needle valve to cause it to close at arelatively slower rate, means actuated by said pressureresponsive deviceon increase in pressure at the outlet of said column to cause arelatively unrestricted flow of uid to flow out of said secondnamedvalve to open it quickly and a relatively l1restricted flow ol' fluid tofiow out of said needle valve to open it at a relatively slower rate,means responsive to an increase in temperature at the outlet of saidcolumn to cause fluid to flow into said needle valve to close it andmeans continuously operable to cause fluid to flow out of said needlevalve to open it, the flow of fluid into and out of said needle valvebeing restricted.

16. In apparatus for precise, batch fractional distillation, adistilling column, means for heating the lower portion thereof, meansfor intermittently cooling the upper portion thereof, a normally open,fluid-operated needle valve operable to control the rate of distillationby controlling the flow of distillate vapors from the column, a vaporline connectingthe upper portion of said column with said needle valveand a second normally open, fluid-operated valve in communication withsaid needle Valve, means :re-

sponsive to pressure change at the outlet of said column to control saidcooling means, a second means also responsive to pressure change at theoutlet of said column, said second pressureresponsive means including apressure-responsive device communicating with the outlet of said column,means actuated by said pressureresponsive device on decrease in pressureat the outlet of said column to cause a relatively unrestricted flow ofuid to flow into said secondnamed valve to close it quickly and arelatively restricted flow of fluid to flow into said needle valve tocause it to close at a relatively slower rate, means actuated by saidpressure-responsive device on increase in pressure at the outlet of saidcolumn to cause a relatively vunrestricted flow of fluid to flow out ofsaid second-named valve to open it quickly and a relatively restrictedow of fluid to flow out of said needle valve to open it at a relativelyslower rate, means responsive to an increase in temperature at theoutlet of said column to cause uid to flow into y said needle valve toclose it and means continuously operable to cause fluid to flow out ofsaid needle valve to open it, the ow of fluid into and out of saidneedle valve being restricted.

17. In apparatus for precise fractional distillation, a fractionaldistillation column, means for applying heat to the lower portion of thecolumn, means for providing a cooling medium in cooling relationship tothe upper portion of the column, and means for controlling the supply ofcooling medium thereto, said controlling means including a manometercommunicating with the outlet of said column, said manometer containingan electrically conductive liquid, a contact member in said manometeradapted to be contacted by the liquid therein on increase of pressure inthe distillation column, and an electrical circuit adapted to be closedon saidl contact to operate said means for controlling the supply ofcooling fluid to the column, said electrical circuit including aperiodic circuit interrupter adapted to open and close said circuitwhile said liquid is in contact with said contact member whereby thesupply of cooling fluid to the column is intermittent.

18. In apparatus for precise fractional distillation, a fractionaldistillation column, means for applying heat to the lower portion of thecolumn, means for providing a cooling medium in cooling relationship tothe upper portion of the column, and means for controlling the supply ofcooling medium thereto, said controlling means including a valve forcontrolling the supply of cooling fluid to the distillation column, anormally open electrical circuit for controlling the operation of saidvalve, said circuit ,including a periodic circuit interrupter which isadav pted to open the circuit intermittently when closed and therebyintermittently open said valve, a manometer communicating with theoutlet of .said column, said manometer containing'an electricalconductive liquid, and a contact member adapted to be engaged by saidliquid on change in pressure in the column to close said valvecontrolling circuit.

19. In distillation apparatus, a distillation column having means forsupply heat at its lower end, means for cooling the column at its upperend, said means comprising a vessel for cooling fiuid in heat-conductiverelationship to the upper portion of the column, a supply container forthe cooling fiuid, means for conducting the cooling fluid from saidcontainer to the cooling` vessel, means for intermittently supplying apressure fluid to the supply container to intermittently force thecooling medium into said vessel, said means comprising a valve forcontrolling the supply of pressure fluid, a normally open electricalcircuit including a periodic circuit interrupter for intermittentlyoperating said valve when the electrical circuit is closed, `a manometercommunicating with the outlet and the column, said manometer containingan electrically conductive liquid, and an electrical contact within themanometer adapted to be engaged by the conductive liquid on rise ofpressure at the outlet of the column to close said electrical circuitand thereby intermittently operate said valve to intermittently supplyfluid under pressure to the supply container of the cooling medium.

20. In distillation apparatus, a batch distillation column having meansfor supplying heat at its lower end, means for cooling-the column at itsupper end, said means comprising a vessel for cooling fluid inheat-conductive relationship with the upper portion of the column, asupply container for the cooling fluid, means for conducting thecooling'fluid from said container to the cooling vessel, and means for,supplying a pressure fluid intermittently to the supply container toforce the cooling medium intermittently into said vessel, said meanscomprising an intermittently operated valve for controlling the supplyof pressure fluid, pressure-responsive means connected with the outletof the column, and means operable thereby on rise of pressure within thecolumn to intermittently operate said valve and thereby intermittentlysupply the pressure uid to said container for the cooling medium, andmeans for venting excess of pressure fluid from said supply container.

21. In combination with a batch distilling column, means for receivingvapors delivered therefrom and for retaining said vapors in vapor `iormwhereby the amount of said vapors received is indicated by changes ofpressure therein, and recording means comprising a temperatureresponsivemember, a thermo-couple connection from said column to saidtemperature-responsive member, a pressure-responsive member, meansinter-connecting said pressure-responsive member with said receiver, anormally open, uidoperated throttlingvalve operable to control the rateof distillation by controlling the flow of distillate vapors from thecolumn and means actuated by said temperature-responsive member on riseof temperature at the top of said column from any previous temperatureto control .the flow of fluid to said valve to decrease the openingthereof.

22. In combination with a batch distilling column, recording meanscomprising a temperatureresponsive member, a thermo-couple connectionfrom said column to said temperature-responsive member, a normally open,fluid-operated throttling valve operable to control the rate ofdistillation by controlling the flow of distillate vapors from thecolumn and means actuated by said temperature-responsive member on riseofA temperature at the top of said column from any previous temperatureto control the flow of fluid to said valve to decrease the openingthereof.

23. In combination with a batch distilling column, distillationrecording means comprising a temperature-responsive member, saidtemperature-responsive member havinga recording arm mechanism adapted tomove on actuation of said temperature-responsive member, a thermo-coupleconnected from said column to said temperature-responsive member,movable means mounted above said temperature-responsive member inadvance of. said recording arm mechanism, a normally open, huid-operatedneedle valve operable to control the rate of distillation by controllingthe flow of distillate vapors from the column and means actuated oncontact of said movable means by said recording arm mechanism on rise,of temperature in said column to control the ow of fluid to said valveto decrease the opening thereof.

24. In combination with a umn," distillation recording means comprisinga temperature-responsive member, said temperature-responsive memberhaving a recording arm mechanism adapted to move on actuation of saidtemperature-responsive member, a thermo-cou ple connection from saidcolumn to said temperyature-responsive member, movable means mountedabove said temperature-responsive member in advance `of said recordingarm mechanism, a normally open, fluid-operated needle valve operable tocontrol the rate of distillation by controlling the flow of column, avapor line connecting the upper portion of `said column with said needlevalve, and a second normally open, duid-operated valve in communicationwith said needle valve through which the vapors from said column areadapted to ilow, said second-named valve being operable to stopdistillation in the column on closing thereof and means actuated oncontact of said movable means by said recording arm mechanism on rise oftemperature in said column to batch distiuing coi-4 distillate vaporsfrom the\ cause iluid to flow into said second-named valve to close it.

25. In combination with a batch distilling column having a. pair ofthermo-couples kpositioned in the upper portion thereof, one above theother, distillation recording means comprising a temperature-responsivemember, electrical connections from said thermo-couples to saidtemperature-responsive member and means intermediate said electricalconnections and said thermo-couples adapted to alternately connect eachthermo-couple with said electrical connections, a normally open,duid-operated valve adapted to control the rate of distillation bycontrolling the ilow of distillate vapors from the column and meansactuated by said temperatureresponsive member on rise of temperature atthe top of said Icolumn from any previous temperature to cause fluid toilow into said valve to decrease the opening thereof.

26. In combination with a batch. distilling having a pair ofthermo-couples positionedin the `upper portion thereof, one above theother, distillation recording means comprising a` temperature-responsivemember, said temperatureresponsive member having a recording armmechanism adapted to move on actuation of said temperature-responsivemember, electrical connections from said thermo-couples to saidtemperature-responsive member and means intermediate `said electricalconnections and said thermo-couples adapted to alternately connect eachthermocouple with said electrical connections, movable means mountedabove said temperature-responsivemember in advance of said recording armmechanism, a normally open, fluid-operated valve adapted to control therate of distillation by controlling the now of" distillate vapors fromthe column and means actuated on contact of said movable means by saidrecording arm mechanism on rise of temperature at the top of said columnfrom any previous temperature to cause fluid to flow into said valve todecrease the opening thereof.

27. In apparatus for precise, batch fractional distillation, adistillation column, means for heating the lower portion thereof, meansfor providing a cooling medium in cooling 'relationship to the upperportion of the column, means for controlling the supply of coolingmedium thereto, said controlling means including a manometercommunicating with the vapor outlet of said column, said manometercontaining an electrically conductive liquid, a contact member in saidmanometer adapted to be contacted by the liquid therein on increaseofjpressure in the distillation column and an electrical circuit adaptedto be closed on said contact .to operate said means for controlling thesupply of cooling fluid to the column, a normally open, iluid operatedvalve in communication with the outlet of said column and through whichdistillate vapors from said column are normally adapted to ilow, a valvecontrol means for controlling the ilow of duid to said valve and therebycontrol the operation of said valve, a second contact member in saidmanometer in contact with said fluid and 'an electrical circuit fromsaid second contact member to said valve controlled means, said valvecontrolled means being normally actuated through said liquid, saidsecond-named contact member, and said second-named electrical circuit toprevent the ilow of fluid to said valve and being operable on Kdecreasein pressure in the distillation column to cause iluid to flow to saidvalve to close it and thereby restrict the flow of distillate vaporstherethrough.

28. In apparatus for precise, batch fractional distillation, adistillation column, means for heating the lower portion thereof, meansfor providing a cooling` medium in cooling relationship to the upperportion of the column, means for controlling the supply of coolingmedium thereto, said controlling means including a manometercommunicating with the vapor outlet of said column, said manometercontaining an electrically conductive liquid, a contact member in saidmanometer adapted to be contacted by the liquid therein on increase inpressure in the distillation column and an electrical circuit adapted tobe closed on said contact to operate said means for controlling thesupply of cooling uid to the column, a normally open, fluid-operatedvalve in communication with the outlet of said column and through whichdistillate vapors from said column are normally adapted to flow, a valvecontrol means for controlling the flow of fluid to said valve andthereby control the operation of said valve, a second contact member insaid manometer in contact winth said fluid and an electrical circuitfrom said second contact member to said valve control means, said valve,control means being normally actuated through said liquid, saidsecond-named contact member, and said secondnamed electrical circuit toprevent the flow of uid through said valve and being adapted to operateto cause uid tol flow to said valve to close it on decrease in pressurein the distillation column and thereby restrict the ow of distillate yvapors therethrough, distillation recording means including atemperature-responsive member, a thermo-coupled connection from saidcolumn to said temperature-responsive member, a second valve controlmeans for controlling the supply of fluid to said valve and therebycontrol the operation of said valve, and means actuated by saidtemperature-responsive member onl rise of' temperature in the columnfrom any previous temperature to actuate said second valve control meansand thereby permit fluid to ow to said valve to close it and thusimpeded the flow of distillate vapors therethrough.

29. In apparatus for precise, batch fractional distillation, adistillation column, means for heating the lower portion thereof, meansfor providing a cooling medium in cooling relationship to the upperportion of the column and means for controlling the supply of coolingmedium thereto, .said controlling means including an electrical circuitoperable in response to an increase of pressure in the column toincrease the supply of said cooling medium to said column, a normallyopen, fluid-operated valve in communication with the outlet of saidcolumn and through which distillate vapors from said/column are normallyadapted to flow, and control means for controlling the flow of uid tosaid valve and thereby control the operation of said valve and, in turn,Athe flow of vapors therethrough, said control means including anelectrical circuit Voperable in response to a decrease of pressure inthe colum to cause fluid to flow to said valve to close it a therebyimpede the flow of vapors therethrough.

30. In apparatus for precise, batch fractional distillation, adistillation column, means`V for heating the lower portion thereof,means for' providing a cooling medium in cooling relationship to theupper portion of the column and means for controlling the supply ofcooling medium thereto, said controlling means including an electricalcircuit operable in response to an 1ncrease of pressure in the column toincrease the supply of said cooling medium to said column, a normallyopen, fluid-operated valve in communication with the outlet'of saidcolumn and through which distillate vapors from said column are normallyadapted to flow, and control means for controlling the flow of fluid tosaid valve and thereby control the operation of said valve and, in turn,the ow of vapors therethrough, said control means including anelectrical circuit operable in response to a decrease of pressure in thecolumn to cause fluid to flow to said valve to' close it and therebyimpede the flow of vapors therethrough, a distillation recording meansincluding a temperature-responsive member, a thermo-couple connectionfrom said column to s aid temperature-responsive member, a second valvecontrol means for controlling the supply of fluid to said valve andthereby control the operation of said valve, and means actuated by saidtemperature-responsive member on rise of temperature in the column fromany previous temperature to actuate said second valve control means andthereby permit fluid to flow to said valve to close it and thus impedethe ow of distillate vapors therethrough.

3l. In apparatus for precise, batch fractional distillation, adistillation column, means for heating the lower portionthereof, meansfor providing a cooling medium in cooling relationship to the upperportion of the column and means for controlling the supply of coolingmedium thereto, said controlling means including an electrical circuitoperable in response to an increase of pressure in the column toincrease the supply of rsaid cooling medium to said column, a normallyopen, fluid-operated valve in communication with the outlet of saidcolumn and through which distillate vapors from said column are normallyadapted to flow, and control means for controlling the flow of fluid tosaid valve and thereby control the operation of said valve and, in turn,the iiow of vapors therethrough, said control means including anelectrical circuit operable in response to a decrease of pressure in thecolumn to cause fluid to flow to said valve to close it and therebyimpede the flow of vapors therethrough, a distillation recording meansincluding a temperatureresponsive member, a thermo-couple connectionfrom said column to said temperature-responsive member, a `second valvecontrol means for controlling the supply of fluid to said valve andthereby control the operation of said valve, and means actuated by saidtemperature-responsive member on rise of temperature in the column of aslittle as one-fifth degree C. from any previous temperature at the topof the column to actuate said second valve control means and therebypermit uid to flow to saidvalve to close it andthus impede the flow ofdistillate vapors therethrough.

32. In apparatus for precise, batch fractional distillation, adistilling column, means for heating the lower portion thereof, meansfor cooling the upper portion thereof, a normally open, fluidoperatedneedle valve adapted to control the rate of distillationby controllingthe flow of distillate vapors from the column, and a vapor lineconthrough, and means responsive to temperature rise at the top of thecolumn from any previous temperature yto control `the flow of iluid tosaid valve to decrease the opening thereof and thereby restrict the iiowof distillate vapors therethrough and consequently decrease the ow ofdistillate vapors from said column.

33. In apparatus for precise, batch fractional distillation, adistillation column, means for heating thev lower portion thereof,`means for providing a cooling medium in cooling relationship to theupper portion-of the column, means for controlling the supply of coolingmedium thereto, said controlling means` including a manometercommunicating with the vapor outlet of said column, said manometercontaining an electrically conductive Iliquid, a contact member in saidmanometer adapted to be contacted by the liquid therein on increase ofpressure in the distillation controlling the supply of cooling fluid tothe valve in communication with the outlet of said s column and throughwhich distillate vapors from column and an electrical circuit adapted tobe 20 said column are normally adapted to ow, a valve control means forcontrolling the -ilow of uid to said valve and thereby control theoperation of said valve, a second contact member in said manometer incontact with said uid and an electrical circuit from said second contactmember to said valve controlled means, said valve controlled means beingnormally actuated through said liquid, said second-named contact member,and said second-named electrical circuit to prevent the flow of -tluidto said valveand being operable on decrease in' pressure in thedistillation column to control the ilow of iluid to said valve todecrease the` opening thereof and thereby decrease the flow ofdistillatevapors from said column.

yWALTER J. PODBIELNIAK.

